Patient healthcare can be greatly improved my providing improved methods of characterizing a disease or condition by providing a diagnosis, prognosis, or treatment selection for the disease or condition. The disease or condition can be detected earlier, or its stage determined to determine what type of treatment should be selected. The disease or condition can be a cancer, such as an epithelial cancer or carcinoma. There are different types of epithelial cells and these can develop into different types of cancer. For example, epithelial cells can constitute a flat surface covering of cells called squamous cells. Additionally, epithelial cells can take a glandular form called adenomatous cells. Also, epithelial cells can form a stretchy layer called transitional cells. Carcinomas make up about 85% of all cancers, and include breast, prostate, lung, colorectal, bladder and ovarian cancers.
Epithelial based cancers usually result in a solid mass or a tumor from which cancer cells migrate throughout the body eventually residing in other locations to establish secondary tumors or metastases. One of the major therapies for cancers resulting in solid tumors is the surgical removal or oblation of the tumor by physical or chemical means. After a cancer is removed from a subject, for example by surgical removal, the monitoring or detection of recurrence of the cancer at the same or secondary sites, can be indicated, so that additional therapies can be employed for treatment should that occur. Likewise, some means of monitoring the success of cancer therapy can be indicated during the treatment phase in order to determine if the therapy is being successful or not and in order to appropriately adapt the therapy accordingly.
There is a need for methods of characterizing cancers, such as epithelial cancers. For example, despite the contribution that the Prostate Specific Antigen (PSA) test has made to the management of prostate cancer, it is plagued by significant shortcomings which result from the antigen being specific for prostate tissue and not for prostate cancer. While the test is highly specific for the PSA antigen, not all prostate cancers release excessive levels of the antigen into the serum. This results in the lack of clinical sensitivity and results in frequent missing of clinically significant cancers with routine PSA examinations.
A normal PSA value is currently considered to be less than 4.0 ng/mL. It is believed that at least 20% of men with significant prostate cancers may have a PSA value less than 4.0 ng/mL. However, since PSA is made by normal, indolent hyperplastic, pre-malignant and malignant tissue, the finding of an elevated PSA (greater than 4.0 ng/mL) does not always indicate cancer. If the serum PSA is in the range of 4.0 to 10 ng/mL there is only a 25-30% chance of finding prostate cancer even through the use of repeated and more thorough biopsies (10-12 cores). The finding of an elevated PSA value frequently results in the subject undergoing an uncomfortable and potentially dangerous transrectal biopsy. It is not uncommon for a man with a significantly elevated PSA to undergo two or more biopsies, in an attempt to find the cause of the elevated serum PSA.
Thus, there is a need for improved methods for characterizing cancer. Provided herein are methods and systems that meet this need, and provides related advantages as well.